Arrests in Vic counter-terrorism raids

400 officers were involved in 19 search warrants on homes across Melbourne.

ABC TV

Police have made four arrests after searching 19 properties in Victoria this morning as part of a counter-terrorism operation.

Authorities say members of the Melbourne-based group have been planning to carry out a terrorist attack in Australia.

More than 400 officers from the Australian Federal Police, Victoria Police, New South Wales Police and ASIO searched homes in suburbs including Glenroy, Carlton, Meadow Heights, Roxburgh Park, Broadmeadows, Westmeadows, Preston, Epping, and in the western district town of Colac.

Police say four arrests have been made but no charges have been laid.

News Ltd is reporting that national security agencies have uncovered a plot by Islamic extremists to launch a suicide attack on an Australian army base, understood to be Holsworthy Barracks on Sydney's western outskirts.

The Australian newspaper said members of the group had been observed carrying out surveillance at the army base and other suspicious activity around defence bases in Victoria.

It is alleged the group is motivated by hostilities in Somalia.

Police have cordoned off a street in Glenroy and are now setting up a forensic tent after searching a property for several hours.